Device for interlocking two elements which are relatively slidable

ABSTRACT

Device for interlocking two relatively slidable elements one of which carries a rack having a slideway and the other slide means movable along the slideway. Two locking means on the slide means are movable between a locking position in which they are engaged in recesses of the rack and an unlocking position on which the locking means are withdrawn from the recesses. A cam associated with the locking means is movable on the slide means for withdrawing the locking means or maintaining the locking means engaged with the recesses. Spring means bias the cam to the position for maintaining the locking means in the recesses and a control means brings the cam to the locking means-withdrawing position. The device is substantially symmetrical relative to a plane which is parallel to the longitudinal direction of the slideway and perpendicular to the guide face of the slideway.

United States Patent 1 [111 3,756,094

Mauron Sept. 4, 1973 DEVICE FOR INTERLOCKING Two 3,445,143 5/1969Swenson 308/36 x ELEMENTS WHICH ARE RELATIVELY SLIDABLE Inventor: GerardMauron, Versailles, France Assignees: Automobiles Peugeot, Paris; RegieNationale Des Usines Renault, Billancourt, France Filed: Nov. 2, 1971Appl. No.: 194,844

Primary ExaminerAllan D. Herrmann AttorneyRobert S. Swecker [57]ABSTRACT Device for interlocking two relatively slidable elements one ofwhich carries a rack having a slideway and the other slide means movablealong the slideway. Two locking means on the slide means are movablebetween a locking position in which they are engaged in recesses of therack and an unlocking position on which the locking means are withdrawnfrom the recesses. A cam associated with the locking means is movable onthe slide means for withdrawing the locking means or maintaining thelocking means engaged with the recesses. Spring means bias the cam tothe position for maintaining the locking means in the recesses and acontrol means brings the cam to the locking meanswithdrawing position.The device is substantially symmetrical relative to a plane which isparallel to the longitudinal direction of the slideway and perpendicularto the guide face of the slideway.

16 Claims, 10 Drawing Figures Patented Sept. 4, 1973 2 Sl10ots-5heet :3

WV mu .R HM U k DEVICE FOR INTERLOCKING TWO ELEMENTS WHICH ARERELATIVELY SLIDABLE The present invention relates to devices forinterlocking two elements which are relatively slidable in a rectilinearor curvilinear path, such devices being in particular of utility for themounting of longitudinally adjustable seats of automobile vehicles.

There has already been described such a device in U.S. Pat. applicationSer. No. 44,784, now U.S. Pat. No. 3,627,253 the main advantages ofwhich are an efficiency which is unaffected by the wear of the componentparts and full safety in both directions of relative displacement owingto the absence of any reaction which would tend to result in anunlocking.

The device disclosed in the aforementioned Patent Application is of thetype having a rack integral with one of the elements and associatedlocking means carried by the other element and comprising in combinationa slideway integral with the rack; slide means integral with the otherelement and movable along the slideway; two locking means carried by andmovable on the slide means between a locking position in which they areengaged in two recesses in the rack and an unlocking position in whichthey are withdrawn from the recesses; a cam movable on the slide meansbetween a first position in which the locking means are withdrawn and asecond position in which the cam maintains them engaged in the recesses;resiliently yieldable means for returning the cam to its second positionand a control device for bringing the cam to its first position inopposition to the action of the resiliently yieldable means.

The present invention concerns an improvement in the device just definedwhich is described in more detail in said patent application so as toimprove its resistance to tearing away and enable it to withstand theconsiderable forces to which a vehicle seat is subjected in particularin the event of an accident when the safety belt exerts considerabletension and/or the seat undergoes a thrust under the impact of thepassenger located behind the seat or under the pressure of an inflatablebag incorporated in the backrest of the seat.

These results are attained in a locking device such as definedhereinbefore which is symmetrical with respect to a plane parallel tothe longitudinal direction of the slideway and perpendicular to theguide face of said slideway.

According to another feature, the slideway has a substantially U- orC-shaped cross section of which the opening is upwardly directed and thetwo flanges define or carry a rack which extends roughly parallel to theslideway. With this symmetrical arrangement, there is an improveddistribution of the forces which affords the desired result.

According to another feature of the invention, the locking meanscomprise two pairs of fingers which are carried by and movable on theslide means, and are received in guide apertures in the cam.

Further features and advantages of the invention will be apparent fromthe ensuing description with reference to the accompanying drawings.

In the drawings FIG. 1 is a side elevational view, with a part cut away,of a first embodiment of the device according to the invention;

FIG. 2 is a cross-sectional view taken on line 2--2 of FIG. 1;

FIGS. 36 are detail cross-sectional views of various embodiments of theslideway;

FIG. 7 is a side elevational view, with a part cut away, of anotherembodiment of the device according to the invention;

FIG. 8 is a cross-sectional view taken on line 88 of FIG. 7;

FIG. 9 is a view similar to FIG. 7 of another embodiment of the devicesaccording to the invention, and

FIG. 10 is a cross-sectional view taken on line 10 10 of FIG. 9.

A first embodiment of the device according to the invention will firstbe described with reference to FIGS. 1 and 2. FIG 1 shows a slideway 31fixed to the floor 32 of a vehicle by means of bolts 33. This slideway,which is better seen in FIG. 2, has a C-shaped cross section defined bya transverse bottom wall 34 and upstanding branches 35 having curved endportions fixed to two racks 36. Thus the slideway 31 and the two racks36 constitute a rigid unit. The top face of the wall 34 constitutesguide face means. A fork having two branches carrying the referencecharacter 37 is integral with the frame of the seat and these twobranches are interconnected in their lower part by a pin 38 having ahorizontal axis X-X. A slide block or shoe 39 is mounted on this pin andhas a lower part which bears on the guide face means or bottom wall 34of the slideway. Apertures 40 and 41 the arrangement of which can beseen in FIG. 1 are formed in the block 39. Slidably mounted in theseapertures are fingers 42 and 43 which-extend on each side of the blockso as to cooperate with the racks 36.

The mechanism for actuating this device comprises a cam constituted bytwo identical side walls or outer portions 44 which are interconnectedin their upper part by a spacer element 45 and pivotably mounted onbearing portions 46 of the block 39. The pivot axis of the cam 44coincides with the axis X-X. Each side wall of this cam is provided withtwo apertures 47 and 48 in which the fingers 43 are guided. In its upperpart, the cam is connected to an actuating cable 49 and is biased by areturn spring 50 which tends to maintain the cam in the position inwhich the fingers 42 and 43 are engaged in the racks 36.

In such a device, the locking is ensured under the same conditions as inthat of the aforementioned Patent Application. In this locking position,the planes (T--T, U-U) tangent to the contact points between the fingersand the racks on one hand and between the cam and the fingers, on theother, are parallel to each other and perpendicular to the plane V-Vcontaining the axes of the fingers and the pivot axis of the cam 44.This avoids any reaction in one direction or the other which would tendto result in the unlocking. It will be understood that the samearrangement is provided for each pair of fingers. To unlock the device,it is sufficient to pull on the cable 49 which pivots the cam 44 aboutthe axis XX in opposition to the action of the spring 50, the fingers42, 43 being then urged downwardly by the upper faces of the apertures47 and 48 and thus disengaged from the recesses between the teeth of theracks 36. Once this unlocking has been achieved, the seat can bedisplaced longitudinally with respect to the slideways 31, the slideblock 39 bearing against and sliding along the bottom wall 34 of thecorresponding slideway.

In addition to the advantages already explained in the aforementionedPatent Application, this arrangement, which is symmetrical with respectto a vertical plane PP, has a substantially increased strength whichenables it to withstand the very large upwardly-exerted tensile forceswhich occur in the event of the vehicle being subjected to a suddenshock, with no danger of the seat becoming separated from its supportwhich is fixed to the floor of the vehicle. This feature considerablyimproves the safety for the occupant of the seat.

It will also be observed that the resiliently yieldable means which werenecessary in the aforementioned Patent Application for disengaging thelocking means from the rack have been dispensed with, this functionbeing performed directly by the side walls of the apertures 47, 48.

In the modification shown in FIG. 3, the slideway 31 also has a C-shapedsection but includes two raised edge portions 51 which are engagedbetween the branches 37 of the fork. The behaviour of the assembly isthus improved since the branches of the fork constitute a positiveretaining means for the branches of the slideway the opening of which isthus rendered impossible.

FIG. 4 shows vertical raised edge portions 52 similar to those shown inFIG. 3 but in this arrangement the racks are formed in strips 53 weldedto these raised edge portions 52 of the slideway 31b.

In FIG. 5, the branches of the slideway 310 terminate at their ends ininwardlyand downwardly-folded edge portions 54 in which the racks aredirectly machined.

In FIG. 6, the arrangement of the racks 55 is similar to that shown inFIG. except that the slideway 31d is constituted by two elements whichare fixed in their lower parts along the flanges 56 by welding or bymeans of bolts 57 which also enable the two elements to be fixed to thefloor.

In another embodiment shown in FIGS. 7 and 8, there are the sameessential component parts but their forms and arrangements are slightlydifferent. The slideway 61 is similar to that shown in FIG. 4, that isto say, it has two branches 62 terminating in vertical edge portions 63welded to strips 64 which are out along their lower edge so as to form arack the slideway 61 and the two racks 64 constituting a rigid unit. Thetwo branches of the fork 65 are, as previously, spaced apart by a pin 66on which a slide block 67 is pivotably mounted. However, incontradistinction to the previous arrangement, this slide block does notbear against the bottom of the slideway but on its edge portions 63 bytwo bearing faces 68, the portions 63 defining guide face means.Further, the slide block 67 itself forms a fork between the branches orouter portions 69 of which the cam 70 is received. There is thepreviously described arrangement of the fingers and guide apertures, theactuating cable device and the retwm spring. This device operates inevery way in a manner similar to that described with respect to theembodiment shown in FIGS. 1 and 2.

In all the foregoing embodiments, the rack teeth and recesses facedownwardly. It will be understood that it is possible to construct adevice in which the rack teeth and recesses face upwardly as shown inFIGS. 9 and 10. In this case, the slideway 71 has a slightly widenedcross-sectional shape (FIG. so as to form two substantialiy horizontalretaining faces 72 which cooperate with corresponding faces 730 on theslide block 73 so as to offer a resistance to tearing-away forces. Theracks are directly machined in the vertical edge portion 74 of thebranches of the slideway. The other component parts of the device haveno particular feature except that the apertures 75 and 76 in the twoside walls or outer portions 77 of the cam have curved shapes so as toensure the correct disengagement of the locking fingers 78 and 79.

The same advantages are obtained as in the previously-describedarrangements.

Having now described our invention what We claim and desire to secure byLetters Patent is 1. In a device for interlocking relatively movablefirst and second structures, comprising in combination, rack means and aslideway combined into a single unit which extends longitudinaliy in aplane and is integral with said first structure, the rack means definingrack recesses and the unit defining guide face means, a slide integralwith said second structure and movable along the slideway in slidableengagement with the guide face means, two locking means mounted on theslide to move between a locking position in which the locking means areengaged in rack recesses in the rack means and an unlocking position inwhich the locking means are withdrawn from the rack recesses, a camassociated with the locking means and mounted to move relative to theslide between a first position in which the locking means are withdrawnfrom the rack recesses and a second position in which the cam maintainsthe locking means engaged in the rack recesses, and means for shiftingthe cam between said second position and first position; the followingfeatures the slideway has in cross section substantially the shape of aC and defines a transverse portion and two branch portions which definean open side through which the slide extends;

the rack means comprise two rack members respectivelyintegral with thetwo branch portions;

one of two elements consisting of said cam and said slide having twoouter portions spaced apart transversely of said plane and the other ofsaid two elements having an inner portion interposed between said twoouter portions;

the two locking means extending transversely of said plane and beingengaged by said two outer portions and engaged by said inner portion andbeing engageable with the two racks;

the two branch portions, the two racks and the two outer portions beingsubstantially symmetrically arranged and disposed relative to said planeand the slide being substantially symmetrical relative to said plane.

2. A device as claimed in claim 1, wherein said open side facesupwardly.

3. A device as claimed in claim 2, wherein the racks have downwardlyfacing operative edges defining the rack recesses.

4. A device as claimed in claim 2, wherein the racks have upwardlyfacing operative edges defining the rack recesses.

5. A device as claimed in claim 2, wherein the branch portions havesubstantially vertical edge portions defining the racks.

6. A device as claimed in claim 2, wherein the branch portions havevertical edge portions to which the racks are fixed.

7. A device as claimed in claim 2, wherein the branch portions haveinwardly extending horizontal flange portions under which the racks areattached.

8. A device as claimed in claim 2, comprising apertures respectivelyprovided in the slide and in the cam, the locking means comprisingfingers having middle portions guided in said apertures and end portionscooperating with the racks.

9. A device as claimed in claim 8, wherein the cam is operative in bothof its directions of movement, in one direction for maintaining thefingers engaged with the racks and in the other direction fordisengaging the fingers from the racks.

10. A device as claimed in claim 1, wherein the second structurecomprises a pin, an upper portion of the slide being rotatably mountedon the pin and the cam being mounted to pivot relative to the slide,means defining apertures in the slide for guiding the locking means, theguide face means comprising a surface on the transverse portion of theslideway.

11. A device as claimed in claim 1, wherein the second structurecomprises a pin, an upper portion of the slide being rotatably mountedon the pin and the cam being mounted to pivot relative to the slide,means defining apertures in the slide for guiding the locking means, theguide face means comprising two bearing faces on upper edge portions ofthe branch portions of the slideway.

12. A device as claimed in claim 1, wherein the second structurecomprises a pin, an upper portion of the slide being rotatably mountedon the pin and the cam being mounted to pivot relative to the slide,means defining apertures in the slide for guiding the locking means, theguide face means comprising bearing faces on the two racks.

13. A device as claimed in claim 9, wherein the cam has said two outerportions and the slide has said inner portion.

14. A device as claimed in claim 9, wherein the slide has said two outerportions and the cam has said inner portion.

15. A device as claimed in claim 1, wherein the second structurecomprises a fork having two branches between which branches the slide ismounted.

16. A device as claimed in claim 15, wherein the branches of the forkhave end portions within which end portions the branch portions of theslideway are disposed whereby the end portions of the branches of thefork are capable of precluding separation of the branch portions of theslideway.

1. In a device for interlocking relatively movable first and secondstructures, comprising in combination, rack means and a slidewaycombined into a single unit which extends longitudinally in a plane andis integral with said first structure, the rack means defining rackrecesses and the unit defining guide face means, a slide integral withsaid second structure and movable along the slideway in slidableengagement with the guide face means, two locking means mounted on theslide to move between a locking position in which the locking means areengaged in rack recesses in the rack means and an unlocking position inwhich the locking means are withdrawn from the rack recesses, a camassociated with the locking means and mounted to move relative to theslide between a first position in which the locking means are withdrawnfrom the rack recesses and a second position in which the cam maintainsthe locking means engaged in the rack recesses, and means for shiftingthe cam between said second position and first position; the followingfeatures : the slideway has in cross section substantially the shape ofa C and defines a transverse portion and two branch portions whichdefine an open side through which the slide extends; the rack meanscomprise two rack members respectively integral with the two branchportions; one of two elements consisting of said cam and said slidehaving two outer portions spaced apart transversely of said plane andthe other of said two elements having an inner portion interposedbetween said two outer portions; the two locking means extendingtransversely of said plane and being engaged by said two outer portionsand engaged by said inner portion and being engageable with the tworacks; the two branch portions, the two racks and the two outer portionsbeing substantially symmetrically arranged and disposed relative to saidplane and the slide being substantially symmetrical relative to saidplane.
 2. A device as claimed in claim 1, wherein said open side facesupwardly.
 3. A device as claimed in claim 2, wherein the racks havedownwardly facing operative edges defining the rack recesses.
 4. Adevice as claimed in claim 2, wherein the racks have upwardly facingoperative edges defining the rack recesses.
 5. A device as claimed inclaim 2, wherein the branch portions have substantially vertical edgeportions defining the racks.
 6. A device as claimed in claim 2, whereinthe branch portions have vertical edge portions to which the racks arefixed.
 7. A device as claimed in claim 2, wherein the branch portionshave inwardly extending horizontal flange portions under which the racksare attached.
 8. A device as claimed in claim 2, comprising aperturesrespectively provided in the slide and in the cam, the locking meanscomprising fingers having middle portions guided in said apertures andend portions co-operating with the racks.
 9. A device as claimed inclaim 8, wherein the cam is operative in both of its directions ofmovement, in one direction for maintaining the fingers engaged with theracks and in the other direction for disengaging the fingers from theracks.
 10. A device as claimed in claim 1, wherein the second structurecomprises a pin, an upper portion of the slide being rotatably mountedon the pin and the cam being mounted to pivot relative to the slide,means defining apertures in the slide for guiding the locking means, theguide face means comprising a surface on the transverse portion of theslideway.
 11. A device as claimed in claim 1, wherein the secondstructure comprises a pin, an upper portion of the slide being rotatablymounted on the pin and the cam being mounted to pivot relative to theslide, means defining apertures in the slide for guiding the lockinGmeans, the guide face means comprising two bearing faces on upper edgeportions of the branch portions of the slideway.
 12. A device as claimedin claim 1, wherein the second structure comprises a pin, an upperportion of the slide being rotatably mounted on the pin and the cambeing mounted to pivot relative to the slide, means defining aperturesin the slide for guiding the locking means, the guide face meanscomprising bearing faces on the two racks.
 13. A device as claimed inclaim 9, wherein the cam has said two outer portions and the slide hassaid inner portion.
 14. A device as claimed in claim 9, wherein theslide has said two outer portions and the cam has said inner portion.15. A device as claimed in claim 1, wherein the second structurecomprises a fork having two branches between which branches the slide ismounted.
 16. A device as claimed in claim 15, wherein the branches ofthe fork have end portions within which end portions the branch portionsof the slideway are disposed whereby the end portions of the branches ofthe fork are capable of precluding separation of the branch portions ofthe slideway.